Enhancing anti-thermal hysteresis ability, response stability and sensitivity of polymer humidity sensor by in-situ crosslinking curing method

Compared with room temperature, the responsive curve of polymer humidity sensor usually presents a nonlinear shift and distortion at higher temperature conditions, this will sharply decrease the accuracy and working stability of polymer humidity sensor. In this paper, an organic–inorganic cross-linked interpenetrating network (c-IPN) between silocane compounds and acrylic prepolymer resin has been constructed to prepare a c-IPN humidity-sensitive material by in-situ crosslinking reaction. The results shows that the prepared c-IPN polymer humidity sensor shows more sensitive in range of 30–90% RH, with higher linearity coefficient of 0.9996 and lower hysteresis coefficient of 1.25% RH. And the c-IPN polymer humidity sensor exhibits more higher stability at higher temperature than that at room temperature. Meanwhile, the temperature coefficient of the c-IPN polymer humidity sensor can decrease to 0.53% RH/°C, along with temperature hysteresis curve linear coefficient increase to (R 2 = −0.999), when (3-aminopropyl) triethoxysilane is used at dosage of 10 wt.% druing crosslinking reaction. This study presents a feasible practical technical solution for developing novel high-performance polymer humidity-sensitive materials and its humidity sensors at wider temperature range.